Publication Date:
2024-03-20
Description:
It has been proposed that ocean acidification (OA) will interact with other environmental factors to influence the overall impact of global change on biological systems. Accordingly we investigated the influence of nitrogen limitation and OA on the physiology of diatoms by growing the diatom Phaeodactylum tricornutum Bohlin under elevated (1000 µatm; high CO2- HC) or ambient (390 µatm; low CO2-LC) levels of CO2 with replete (110 µmol/L; high nitrate-HN) or reduced (10 ?mol/L; low nitrate-LN) levels of NO3- and subjecting the cells to solar radiation with or without UV irradiance to determine their susceptibility to UV radiation (UVR, 280-400 nm). Our results indicate that OA and UVB induced significantly higher inhibition of both the photosynthetic rate and quantum yield under LN than under HN conditions. UVA or/and UVB increased the cells' non-photochemical quenching (NPQ) regardless of the CO2 levels. Under LN and OA conditions, activity of superoxide dismutase and catalase activities were enhanced, along with the highest sensitivity to UVB and the lowest ratio of repair to damage of PSII. HC-grown cells showed a faster recovery rate of yield under HN but not under LN conditions. We conclude therefore that nutrient limitation makes cells more prone to the deleterious effects of UV radiation and that HC conditions (ocean acidification) exacerbate this effect. The finding that nitrate limitation and ocean acidification interact with UV-B to reduce photosynthetic performance of the diatom P. tricornutum implies that ocean primary production and the marine biological C pump will be affected by OA under multiple stressors.
Keywords:
Alkalinity, total; Alkalinity, total, standard deviation; Aragonite saturation state; Bicarbonate ion; Bicarbonate ion, standard deviation; Bottles or small containers/Aquaria (〈20 L); Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon, inorganic, dissolved; Carbon, inorganic, dissolved, standard deviation; Carbonate ion; Carbonate ion, standard deviation; Carbonate system computation flag; Carbon dioxide; Carbon dioxide, standard deviation; Catalase activity, standard deviation; Catalase activity, unit per cell; Catalase activity, unit per protein mass; Charophyta; Chromista; Coulometric titration; Damage/repair ratio; Damage/repair ratio, standard deviation; Damage rate; Damage rate, standard deviation; Effective quantum yield; Effective quantum yield, standard deviation; Exponential rate constant for recovery; Exponential rate constant for recovery, standard deviation; Figure; Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Laboratory experiment; Laboratory strains; Light; Macro-nutrients; Non photochemical quenching; Non photochemical quenching, standard deviation; North Atlantic; OA-ICC; Ocean Acidification International Coordination Centre; Ochrophyta; Partial pressure of carbon dioxide, standard deviation; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; pH, standard deviation; Phaeodactylum tricornutum; Photosynthetic carbon fixation rate, per cell; Photosynthetic carbon fixation rate, per chlorophyll a; Photosynthetic carbon fixation rate, standard deviation; Phytoplankton; Potentiometric; Primary production/Photosynthesis; Protein per cell; Proteins, standard deviation; Repair rate; Repair rate, standard deviation; Salinity; Single species; Species; Superoxide dismutase activity, standard deviation; Superoxide dismutase activity, unit per cell; Superoxide dismutase activity, unit per protein mass; Table; Temperature, water; Time, standard deviation; Time in minutes; Treatment; Ultraviolet-a radiation-induced inhibition of carbon fixation; Ultraviolet-a radiation-induced inhibition of carbon fixation, standard deviation; Ultraviolet-a radiation-induced inhibition of effective photochemical quantum yield; Ultraviolet-a radiation-induced inhibition of effective photochemical quantum yield, standard deviation; Ultraviolet-b radiation-induced inhibition of carbon fixation; Ultraviolet-b radiation-induced inhibition of carbon fixation, standard deviation; Ultraviolet-b radiation-induced inhibition of effective photochemical quantum yield; Ultraviolet-b radiation-induced inhibition of effective photochemical quantum yield, standard deviation
Type:
Dataset
Format:
text/tab-separated-values, 7864 data points
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